/*
const x = {
  updaters:new Set(),
  batchUpdate(){
    console.log('batchUpdate');

    for (const updater of this.updaters) {
      console.log('updater.updateClassComponent:',updater.updateClassComponent);
    }
  }
}

x.updaters.add({a:1})
x.updaters.add({b:2})
x.updaters.add({c:3})

x.batchUpdate()
*/


/*
const fn1 = () => {
  console.log(1);
};
const fn2 = () => {
  console.log(2);
};

const arr = [];
arr.push(fn1);

console.log('arr.includes(fn1):',arr.includes(fn1)); //true
console.log('arr.includes(fn2):',arr.includes(fn2)); //false
*/


/*const arr = [1]
arr[3] = 123;
console.log(arr); //[ 1, <2 empty items>, 123 ]

console.log([].every(item => item === '1')); //true*/


const arr = [1];
const [x, y] = arr[1];
console.log(x, y); //TypeError: undefined is not iterable (cannot read property Symbol(Symbol.iterator))

